collaborators

5 papers

math.AP2026

Supersolution Construction and Optimal Hardy Inequality for Fractional Laplacians

Philipp Hake, Matthias Keller, Felix Pogorzelski

We give a new criterion to show optimality of Hardy weights for general operators on graphs via the supersolution construction. For Laplacians on graphs without killing terms this…

math.AP2026

A Liouville Theorem for Domains in Graphs

Philipp Hake, Matthias Keller, Felix Pogorzelski +1

We show a Liouville theorem for domains in graphs with Dirichlet boundary conditions. More specifically, we characterize the non-existence of non-zero bounded harmonic functions. S…

math.FA2026

The complex property of the boundary operator on simplicial complexes

Philipp Bartmann, Matthias Keller

We study the complex property of the boundary operator on a weighted, infinite, and possibly non-locally finite simplicial complex. We give a char…

math-ph2026

Positive Criticality and Optimal Hardy Inequality for Fractional Laplacians

Philipp Hake, Matthias Keller, Felix Pogorzelski

We characterize positive critical Hardy weights for general Laplacians on weighted graphs. We then apply this result to fractional Laplacians on general graphs and use the characte…

math.FA2026

Graphs at infinity: Liouville theorems, Recurrence and Characterization of Dirichlet forms

Matthias Keller, Daniel Lenz, Marcel Schmidt

We survey recent results on graphs and their Laplacians related to the behavior of the graph at large. In particular, we focus on Liouville theorems, recurrence and characterizatio…